窗体上有一个名称为Command1的命令按钮,一个名称为Text1的文本框。编写如下程序: Private Sub Command1_Click() Dim x As Integer x = Val(InputBox("输入数据")) : Text1 = Str(x + fun(x) + fun(x)) End Sub Private Function fun(ByRef n As Integer) If n Mod 3 = 0 Then n = n + n Else n = n * n End If fun = n End Function 对于上述程序,以下叙述中错误的是